/*
 * Copyright 2014 Netflix, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.netflix.servo.util;

import org.testng.annotations.Test;

import java.util.Arrays;
import java.util.Collections;
import java.util.Iterator;
import java.util.NoSuchElementException;

import static org.testng.Assert.assertEquals;
import static org.testng.Assert.assertFalse;
import static org.testng.Assert.assertTrue;

public class StringsTest {

  @Test
  public void testIsNullOrEmpty() throws Exception {
    assertTrue(Strings.isNullOrEmpty(null));
    assertTrue(Strings.isNullOrEmpty(""));
    assertFalse(Strings.isNullOrEmpty(" "));
    assertFalse(Strings.isNullOrEmpty("adsf"));
  }

  private static <T> Iterator<T> emptyIterator() {
    return new Iterator<T>() {
      @Override
      public boolean hasNext() {
        return false;
      }

      @Override
      public T next() {
        throw new NoSuchElementException();
      }

      @Override
      public void remove() {
        throw new IllegalStateException();
      }
    };
  }

  @Test
  public void testJoin() throws Exception {
    assertEquals(Strings.join(", ", emptyIterator()), "");
    assertEquals(Strings.join(", ", Collections.singletonList(1).iterator()), "1");
    assertEquals(Strings.join(", ", Arrays.asList(1, 2).iterator()), "1, 2");
  }
}
